Suspicious Duke Malware DLLs Written to Windows Tasks Directory (via file_event)

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1574.001DLL
Persistence
- T1574.001DLL
Priv Esc
- T1574.001DLL
Defense Evasion
- T1574.001DLL
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects the Duke malware support DLLs being written into the Windows Tasks directory during the APT29 German Embassy campaign side-loading chain. Dropping Mso.dll and AppVIsvSubsystems64.dll into C:\Windows\Tasks stages the side-loading pair for msoev execution. DLL creation in this task directory is abnormal and indicates payload staging.

Reporting behind it

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Suspicious Duke Malware DLLs Written to Windows Tasks Directory (via file_event)

Pivot detection · T1574.001 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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